Loom fork filling motion



1949- s. E. CLENTIMACK LOOM FQRK FILLING MOTION 2 Sheets-Sheet 1 FiledOct. 4, 1947 INVENTOR. GEORGE E. C'LENTJMACK 1949. G. E. CLENTIMACK LOOMFORK FILLING MOTION 2 Sheets-Sheet 2 Filed Oct. 4, 1947 7- T a R m M 5Mm mm 2 MW M I 58 T l h L 1 5 0 N A 7 m h f 6 5 W N F 5 a 1M 1 u o m u .7a 9 I u. n u R 5 JI TFJ ZLIJTI I w o e 6 .2 a E Y 8 B 7 T W I W ma -.1.a, loss 2,481,493 LOOM FORK FILLING MOTION George E. Clentimaek.Plainville, Mala,

to Draper p ration.

poratlon of Maine Hopedale, Ma... a car- Applicatlon October 4, 1947,Serial No. 777,981 14 Claims. (Cl. 139-375) This invention relates toweaving looms, and more specifically to fork filling motions havingfilling fork devices for detecting absence or breakage of the filling ator in the warp shed in such looms.

Weaving looms customarily are equipped with one or more fork fillingmotions for initiating a change in the operation of the loom upon theoccurrence of a filling fault, such as absence of a filling thread, orbreakage thereof. in the warp shed. These motions are of two classes,namely.

side fork filling motions and center fork filling motions. Bide forksare employed, sometimes one at each side of the loom and in otherinstances at but one side of the loom, to initiate loom stoppage orfilling replenishment in the event of occurrence of one of the mentionedfilling faults. Center 'forks, located usually near the center of thelay of the loom, are employed to initiate stoppage of the loom ifexhaustion or breakage of filling within the shed occurs.. While, aswill become evident hereinafter, certain features of my invention areapplicable to either type of fork filling motion, the invention isprincipally directed toward and will be described in connection with acenter fork filling motion for looms.

Heretofore center fork filling motions have included as actuators suchmechanical means as cam and follower lever structures. push or pump rodstructures, and driving links connected to a part of the breast beam ofthe loom. As is well known to those skilled in the weaving art, all ofthose known modes of operation of center fork filling motions presentseveral common disadvantages and defects. A loom filling motion mustoperate in a certain time-relationship with other loom motions: and dueto the inherent nature of -ordinary loom construction and operation thefilling fork must perform its operation of detecting the condition ofthe filling during a very short periodof time. In high speed loomsespecially, the mentioned requirements of fork operation necessitate'very fine adjustment of the cams, links, or pump rod'nrcehanisms whichraise .and lower the fork in its rising and filling detecting movements.In many instances the adjustments must be made frequently, and since-most fork actuating structures are inside the loom framework andbetween the cloth roll and the warp beam, it is readily perceived thatadjustments are a source of considerable inconvenience and annoyance.Another disadvantage inherent in the prior art structures is that the:adjustments must be made with the loom quiescent, which makes necessarya trial and error type of repeated adjustment procedure which continuesuntil a satisfactory adjustment is secured. Such procedures areobviously time-consuming and bothersome. A further disadvantage sufferedby prior filling motions of the center fork type is that the periodduring which the fork was raised could not readily be varied at theterminal end of the period. Another undesirable feature of existingknown types of filling motions is that the parts are numerous and manyof them relatively heavy. Furthermore, all of the mentioned mechanicalmeans for raising and lowering the fork tines necessarily operate soslowly that they allow an all too brief period of time for setting themechanical, loom-stoppage initiating means into active position. It willbe understood that the fork tines are lowered to determine the conditionof the filling as the lay is at or near back center position and that itis desirable to stop the loom before the lay reaches front centerposition if a filling fault exists.

With the aforementioned and other undesirable characteristics of priorfork filling motions generally and more particularly of center forkfilling motions in mind, it is an object of the invention to provide anovel fork filling motion which does not possess those undesirablecharacteristics. Another object of the invention is to provide a centerfork filling motion of simple lightweight construction. An additionalobject is to provide a center fork filling motion which is capable ofeasy and accurate adjustment. Another object is to provide a center forkfilling motion which may be easily and accurately adjusted while theloom is in operation. A further object is to provide a center forkfilling motion whose timing may be regulated without substitution ofcams or other parts. Another object is to provide a fork filling motionin which the portion of the loom cycle during which the fork is raisedmay readily be varied. Another object of the invention is to provide afilling fork tine and induction-repulsion means actuating the fork tine.Another object is to provide a magnetically actuated filling forkstructure for a fork filling motion. An additional object is to providean electromagnetically actuated, electrically controlled, center forkfilling motion.

The objects of the invention, including both those specifically statedhereinabove and others that will hereinafter become apparent, areattained by the invention, a preferred embodiment of which is fullydisclosed in the following description and accompanying drawings forminga part of this specification.

In the drawings:

Fig. l is'a plan view of a equipped with center filling fork devices ingto the principles of the invention;

Fig. 2 is a sectional view on line 2-4 of Fig. I, viewed in thedirection indicated by-the arrows:

Fig, 3 is a view in elevation as viewed in the direction of arrow A ofFig.1, of structure shown in that figure but removed from the lay beam;

Fig. 4 is a view of the structure shown in Fig. 3, as viewed from theright in the latter figure;

Fig. 5 is an exploded view in isometric projection of a filling forkarmature and tines, and of a switch cam for actuation by the forkarmature;

Fig. 6 is an isometric view of a magnetizabie field piece and field coilforming a part of the fork filling motion according to the invention;

Fig. 7 is an electrical circuit diagram including a schematicillustration of electrical circuit elements and connections employed inthe center fork filling motion according to the preferred embodiment ofthe invention;

Fig. 8 is a view in elevation of an electrical timer structure with acover plate and cover plate lock removed;

Fig. 9 is a sectional yiew of the timer structure illustrated in Fig. 8,"taken along line 9-9 in the latter figure, with the cover plate andcover lock ring added; a,

Fig. 10 is a rear view or the timer structure with a collar and shaftcoupling removed;

Fig. 11 is a view in elevation, partly in section, of the timerstructure, showing details of the interior construction; and

Fig. 12 is a fragmentary view of timer structure.

Referring to the drawings, and more particularly to Figs. 1 through 4,there is depicted a centrally located segment of a lay'beam I0 uponwhich are mounted the customary reed ii and shuttle race plate l2. Thelay beam and race plate are cut away as usual to provide a fork well i3into which the tines ll of a filling fork may move if not prevented fromso doing by an intact filling thread or yarn i5 extending along the raceplate. As is well known, a single fork tine may be employed, or aplurality, as desired or needed. The structure thus far enumerated iswell known to those skilled in the art and may be of conventionaldesign. Only so much of the conventional loom structure is shown as isnecessary to a clear understanding of the invention. Secured to thefront side of the lay beam by any suitable means, as by screw means i6,i1, is a filling fork structure comprising the mentioned tines andincluding a frame i8 of iron or other magnetizable material, which mayconveniently be formed by casting. The frame is formed with a U-shapedsupport l9 through the legs of which are bored or otherwise provided,aligned holes providing bearings for a fork spindle 20. The spindlesupports for pivotal motion therewith an induction-repulsion forkarmature 2i to which the tines I4 are secured in any suitable manner, asby means of slots and screws 22 (see Fig. 5). Armature 2! is secured tothe spindle so as to rotate therewith, conveniently by being pressfittedupon the spindle. Carried by a portion of spindle extending beyondsupport I9 is a switch cam 23 which is secured to and caused to rotatewith the spindle by any suitable means, such as a set screw 24. Firmlysecured to support l9 by any appropriate means, as by screw means 25 isan electrical switch 26, preferably of the snapacting varietycommercially available under such portion of a loom lay accordtradenames as Micro-Switch" and "Mn- Switch." Switches of this type aresupplied with three or more terminals providing a normally ciosed" pairof terminals and a normally "open" pair of terminals. Switch 23 and cam23 are so positioned relatively to each other and the cam so positionedon spindle 20, that when the tines of the fork are in thread engagingposition (indicated at B in Fig. 2), or above that position, the switchwill be in open-circuit condition relative to the electrical circuitinwhich it is connected, and when the tines are allowed to fall bygravitational action or be lowered as by a conventional weft fork spring(not shown) into the well, as when they engage a broken filling threador when no thread has been deposited on the race plate (as indicated atC in Fig. 2), the switch will be caused or allowed to assume aclosed-circuit condition relative to the circuit.

Secured to and supported by frame [8 is an electromagnet core or fieldpiece 21 preferably formed of thin laminae of soft iron, and of shapeindicated in Figs. 2 and 6. The laminae may be secured together to makea unitary element, as by rivets 28, 23, aided by screws 30, 3| whichserve to secure the field piece to frame i8. Screws 30, 3| pass eachthrough a respective one of holes 32, 33 formed in field piece 21 (seeFig. 6) and are received in respective tapped holes formed in the upperportion of frame I8 and in a downwardly extending flange portion 34 ofthe frame. The curved leg 35 of field piece 21 is formed with arcuateupper and lower surfaces 36, 3'! concentrically arranged about the axisof spindle 20 as a center. Fork armature 2i is provided with a dependingplate-like part 38 provided with an aperture 39 accommodating the curvedleg 35 of the field piece. (See Fig. 5 The plate-like part 38 is ofnon-magnetic material of good electrical conductivity and preferably oflow specific gravity, such as aluminum, thus forming around the aperture39 an electric coil having a. single shortcircuited turn in theelectrical sense. Aperture 39 is of such dimensions as to allow armature2| to oscillate freely about the axis of spindle 20 with clearancebetween the armature and leg 35 of the field piece, but preferably theopening is as small as the mentioned clearance will reasonably permit.

Surrounding and closely fitting the lower part of leg 35 of the fieldpiece is a field coil 40 (see Fig. 6) formed of a plurality of turns ofinsulated electric conductor, such as aluminum or copper wire, the coilbeing suitably insulated and pro tested as by means of a tape wrappingii. The field coil is arranged to be periodically energized by rapidlyfluctuating current of suitable intensity in a manner and by means morefully described hereinafter, through coll leads Y, Z. When so energized,a rapidly varying magnetic field is set up by the coil, the magneticallypermeable structure formed by frame 18 and field piece 21 forming a goodflux path and allowing a relatively strong fluctuating field to becreated. Since the current in 0011 40 is rapidly fluctuating there is acontinually changing magnetic fiux cut by the short-circuited turnformed by armature part 38, which results in a flow ofinducedelectricalcurrent in the short-circuited turn. The last mentioned current createsa magnetic field which tends to oppose or buck the first mentionedmagnetic field, causing the short-circuited turn formed by part 38 totend to be repulsed by and hence to move away from coil 40. Being freeto so move, part 38 moves to the left as viewed in enemas Figs. 2 and 3,rotating the fork armature of which it is a part about the axis ofspindle and consequently raising tines it above race plate l2 and into aposition indicated at D in Fig. 2. As soon as the current supply to coilis cut off, gravitational forces act to lower tines H to fillingengaging position. Obviously, gravitational forces may, if desired, beaided by conventional filling fork spring means (not shown). It will beseen that by suitably opening and closing the current supply circuit forcoil 40 in timed relation to the passage of the filling-layer orshuttle, the tines may be raised to permit passage of the weft layer andallowed to return to filling engaging position to detect presence orabsence of an intact filling. Further it will be seen that if the tinesare permitted to fall or be lowered into the fork well by absence of anintact filling, switch cam 23 will be rotated to a position causingswitch 26 to assume a closed circuit condition. Through suitableinstrumentalities more fully disclosed hereinafter, the loom may thus bestopped, or other loom changes initiated.

To supply fluctuating current (which may be pulsating direct current oralternating current) at the proper times and during the proper periodsto coil MI, and to permit switch 26 to properly control initiation of anoperational change in the loom, such as loom stopping, electricalcircuit means and appurtenant structure are provided and connected asindicated diagrammatically in Fig. 7. Referring to the latter figure,rapidly fiuctuating electric current is made available to coil 40 bymeans of a power transformer T whose primary P may conveniently beconnected to the loom power supply circuit, not shown, preferably butnot necessarily through the conventional master switch controlling theloom driving motor circuit, not shown. The transformer may have a tappedsecondary but preferably has a plurality of secondary windings includinga secondary SA whose terminals are connected to suitable conductors orleads as indicated to supply current to coil 40 in series with timercontacts Cl, C2 which are hereinafter more fully described andexplained. It will be noted that engagement (closing) of the twocontacts allows current to flow through, and energize, coil 40.Continuing reference to Fig. 7, fork armature 2| is diagrammaticallyillustrated as in a position wherein tines ll are raised and switch cam23 is positioned to cause or allow switch 26 to assume an open-circuitcondition. Rotation of armature 2| by downward movement of the tinesinto the fork well results in cam 23 taking a position wherein switch 26assumes a closed-circuit condition, allowing current to flow from anadditional transformer secondary SB through a normally closed switch 8of any suitable conventional type to and through a stop motion magnetcoil M of a suitable conventional electrical loom stop motion, throughswitch 26, through timer contacts C3, C4 which are hereinafter morefully described and explained, and back to and through secondary SB, theenumerated parts being electrically connected by suitable insulatedelectricalconductors as indicated. While switch 26 is diagrammaticallyillustrated as with its normally open terminals connected in circuitwith coil M and secondary SB, it will be evident that cam 23 may be soset that the circuit may be operated with the normally closed" terminalsof switch 26 connected in series with coil M and secondary 8-13. In thismode of operation cam 23 would cause switch 26 to assume a positionwherein the normally 6 closed" terminals thereof would remainelectrically disconnected until the fork tines descended into the forkwell, whereupon the cam would permit or cause the switch to assumenormal position with the normally closed terminals electricallyconnected. In the case of either of the described modes of operation ofcam 23 and switch 26, closure of the circuit through the latter resultsin energization of stop motion magnet coil M and initiation of loomstopping action thereby, assuming for the moment that contacts C3, C4are closed. The loom stopping action is of itself well understood in theart and need not here be further described.

It will be understood that transformer '1 may be replaced byother.equivalent means, such as a rectifier circuit or a vibratorcircuit, to supply pulsating direct current or alternating current tocoil 40 and to supply either pulsating or continuous current power tocoil M. Further, it will be obvious that any suitable power voltages andcurrents may be employed, the circuit elements being designed andinsulated in accordance 'with the values chosen. Common voltages usedfor loom motor operation are volts, 220 volts and 440 volts, for any ofwhich the primary of transformer T may be wound. Commonly employed loomauxiiiary and stop motion voltages range from 4-.to 16 volts, for any ofwhich the transformer secondaries SA and 8-43 may be wound. Coils 40 andM may be constructed for 50 watts power consumption, and may differ fromthat value as conditions warrant or require. While equivalent means forsupplying pulsating current to coil 40 and current to coil M ma beemployed, an alternating current transformer is preferred for itssimplicity, cheapness and other obvious characteristics.

Referring to F1 is. 8 through 12, there is illustrated means including apreferred form of timer structure includin the aforementioned pairs ofcontacts Ci, C2 and C3, C4, which structure allows of easy and preciseadjustment whereby the time of energization and period of energizationof field coil 40, and the portion of the loom oper-: ating cycle duringwhich switch 26 is permitted to be potentially capable of completing acircuit through magnet coil M, may be easily and precisely regulated tosecure optimum results in detecting filling faults and effecting earlyloom stopping. A plate-like bracket 50 of which only one end is shown,and of any desired shape and size is secured to any convenient fixedpart of the loom frame (not shown), preferably adjacent the loomside andext-ending outwardly to a position near the end of the crankshaft of theloom. Mounted on bracket 50 by means of headed screws 6|, 62 passingthrough and movable in respective arcuate apertures 53, 54 in thebracket is a timer cup 56 having tapped holes as indicated to receivethe screws iii, 52. The timer cup is preferably of cylindrical exteriorconfiguration and is provided with an axially extending bore 56 passingthrough the base of the cup and through an integral bearing boss 51extending from the base of the cup, see Fig. 9. Bracket 50 is providedwith a circular central aperture 56 aligned with and of the samediameter as here 56, and about which are formed the arcuate openings 61and 54. Fig. 10. Tightly engaging the inner wall of the cup and restingon a shelf 58 formed on the inner wall is a disk 60 of electricalinsulation, e. g. synthetic resin, some of which are sold under thenames. Micarta or Bakelite. The disk is provided with a centrallylocated aperture align;-

BJOLGQS ed with bore 80. The latter bore and the aperture alignedtherewith rotatably accommodate'a timer cam shaft 8|. The shaft extendsoutwardly of the base of the timer cup and through the aperture 58 inbracket 50 and has secured to it at its outer end one member, SI, of acoupling by means of which the shaft is given rotative movement by asecond and similar coupling member S2 secured to, or otherwise driven intimed relationship with, the conventional loom crankshaft, not shown.Holding shaft il in position in the bore, and retaining disk 60 againstshelf 59-, is a collar 62 outside of and bearing against a face ofbracket 50, and a timer cam 63 secured on the inner end of the shaft.The collar and the cam may be secured in .proper positions on the shaftby any suitable means, as by set screws as indicated. The cam preferablyhas a circular hub to bear against disk 60 as indicated, and may be ofeccentric shape.

Mounted on disk 60 is a pair of screw pivots N, 5, which are secured tothe disk by each passing through respective holes formed therein andhaving locking nuts thereon turned tight against the disk as indicatedin Fig. 9. These screw pivots serve as electrical terminals and pivotmounts for respective breaker arms 66, 61 having looped ends closelysurrounding the respective pivots between shoulders thereon, said armsbeing formed of suitable electrically conductive spring material such ascopper-beryllium alloy or steel; each of the arms having secured theretoas by means of rivets a respective cam follower block 88, 69 formed of asuitable wear-resistant electrical insulation material such as have beenmentioned above. Holding the two follower blocks into contact with theaforementioned timer cam 63 is a coil spring 10 hooked at each end in asuitable hole formed in a respective one of the blocks. See Fig. 8.Breaker arm 66 has secured to it as by brazing the aforementionedcontact Cl, which is arranged for electrical co-action with its matingcontact C2 which in turn is secured to or forms an end of an adjustingscrew 1| carried by and threaded through a tapped opening in anelectrically conductive terminal mount 12 suitably secured to disk 60 asby a screw 13 and a rivet I4 which conveniently may form a terminal forcontact C2. Screw ll preferably is made of sufficient length to extendoutwardly from its mount through an aperture 15 formed in cup 55 (seeFig. 12). The aperture may be fitted with a suitable bushing 16 ofelectrical insulation, the interior diameter of the bushing being suchas to easily pass screw 1 I. Thus it is evident that screw H may beadjusted from the exterior of the timer cup to move contact C2 toward oraway from its mate, C l, for a purpose more fully explained hereinafter.Across the terminals formed by rivet H and screw pivot 64 there ispreferably connected a spark-suppressing resistor RA, of about 750 ohmsresistance; and suitable insulated leads W, X from the terminals extendout of the timer cup through an insulating bushing 11 mounted in anaperture 18 formed in the wall of the cup. Similarly to the case of arm66 and appurtenant structure, breaker arm 61 has secured to it contactC3 which coacts with its mate C4 on an adjusting screw 19 threadedthrough an opening in a conductive terminal mount Ill secured to disk 60by screw II and rivet 82. Similarly, terminals formed by screw pivot 65and rivet 82 have connected thereacross a 750 ohm resistor RB, and haveconnected thereto insulated leads N, 0, extending out of the timer cupthrough bushing l1.

Screw I! is extended outwardly of the timer cup through an insulatingbushing 83. Contacts C8, C4 are employed to open the circuit throughstop motion magnet coil M during that period of each loom cycle when thefilling is moved from under the fork tines as it is beaten into the fellof the cloth being woven. During that period, commencing a short timeprior to front center position of the lay and terminating a short timeafter front center, the fork tines are forced into the fork well andthus cause switch 26 to assume a closed circuit condition. Separation ofcontacts C2, C4 during the entirety of that period prevents switch 26from initiating an undesired loom stoppage. The above mentionedresistors are of such resistance as to pass insuflicient current tocause operative energization of coils 40 and M.

Cam i3 is, as above indicated, preferably of eccentric configuration;and being secured to shaft 6| will rotate synchronously with the loomcrankshaft and thereby cause oscillation of breaker arms 66, 61 abouttheir respective pivots to cause opening and to allow closing of therespective pairs of contacts Cl, C2 and C3, C4, under the influenceofspring I0. It is evident that, since a single cam is employed to operateboth breaker arms, and since both the times of closing and opening andthe duration of engagement of contacts CI, C2 are quite different fromthose of contacts C3, C4, a particular arrangement of the parts isnecessary. It is desirable that contacts Cl, C2 close at a point in theloom cycle corresponding to about 45 of crankshaft revolution past frontcenter as the lay moves toward top center position, to cause raising ofthe fork tines as soon as practicable after they clear the fell of clothand before filling laying or shuttle picking occurs, at or near the topcenter position of the lay; and it is desirable that those contacts openat a point in the cycle corresponding to about past top center positionof the lay so the tines may move down into detecting position as soon aspossible after the filling has been laid past the fork well. These timesof closing and opening of contacts Cl, C2 vary somewhat for differentloom speeds, and are different for different widths of looms. It thus isimportant, especially in high speed looms, to be able to widely vary andto precisely adjust the time of closure of contacts Cl, C2 and theduration of the period of their closure. It is desirable that contactsC3, C4 open the stop motion magnet circuit some time followingtermination of the active filling detection period and prior to the timethe filling is moved from under the fork (the former time correspondsroughly to.- a point in the loom cycle 60 before front center position),and to maintain the circuit open until after the fork tines have beenlifted from the fork well (which occurs somewhat prior to a point in theloom cycle corresponding to 90 past front center position of the lay).Thus is it seen that contacts CI, C2 should be closed from approximately45 .past front center to approximately 90 past top center, or roughlythrough of rotation of the eccentric or cam 63, this period having itsmiddle at about 22 past top center; whereas contacts C3, C4 should beclosed from approximately 90 past front center to approximately 30 pastbottom center, or roughly through 210 of rotation of the cam, thisperiod having its middle at about 15 past rear center. Since the middlesof the respective periods of closure of contacts Cl, C2 and C3, Cl. arethus roughly 83 apart, the highest point 9 of cam 09 should contactfollower block about 83 ahead of the point at which it will latercontact follower block 09. Accordingly. the follower blocks are soshaped and placed that their lines of contact with the cam are 83'apart. as illustrated in Pig. 8. In this arrangement it is assumed thatcam shaft II will rotate in the direction indicated in the arrow in Fig.9. The

durations of time or portions of the 360' of rotation of the cam duringwhich the respective pairs of contacts are in contact may readily beadjusted by moving respective screws ll, ll, in or out, toward or from,their mating contacts, as is deemed to be obvious, each spring breakerarm bending slightly and returning to normal condition during the periodof interengagcment of its associated contacts. Thus by adjustment ofscrew ll, contacts Cl, C! may be set to engage during exactly 185' ofrotation of the cam, or more, or less. as conditions warrant or require.After screw H has thus been adjusted to provide the proper period ofclosure of Cl, CI, the precise time at which closure commences may beadjusted by loosening screws II, I! and rotating the timer cup aboutshaft OI, thus rotating breaker arm II and follower block if about thecam, until the proper timing has been secured. Thereafter screws I, I!are tightened to secure the cup in adjusted position. To facilitateinitial adjustment of the timer cup andto allow of ready duplication ofa previous adjustment thereof, an index mark 04 is scribed on bracket 5.and cooperating marks II are formed on the outside face of the cup atthe base thereof, as indicated in Fig. 11. Since the times of closureand openin of contacts C9, C4 are not critical but may be shifted asmuch as of each cam revolution without detrimental results, it is seenthat the precise adjustment of the timing of contacts Cl, C! need notdeleteriously affect the timing of contacts C3, C4. The duration of theperiod of closure of the latter contacts may, of course, be widelyvaried by adjustment of screw 19.

It will be understood that screws H, I! may be secured in their terminalmounts by any suitable means as by lock nuts (not shown), but preferablythe screws and mounts are made with tightly interfitting surfaces, whichallows of ready external adjustment of the screws.

The contained structure within cup I! may conveniently be protected fromdust or accidental damage by a cover plate ll (Fig. 11) resting on ashelf 01 formed on the inner wall of the cup, the plate being held inplace by an expansible internal spring locking ring 93 hearing in agroov '9 formed in the inner face of the cup.

Initial setting, adjustment, and operat'on of the filling motion maybriefly be summarized as follows. With screw 'H adjusted so the cam willcause closure of contacts Cl, C! during only approximately l of each 360it rotates, and screw 19 adjusted so contacts CI, Cl will be closed bythe cam during 210 of each complete rotation, and with screws I, 52positioned approx mately in the centers of their respective slots 53, 54and tightened, and with the lay of the loom advanced about of crankshaftrotation toward top center from front center, cam 83 is loosely rotatedon shaft ll until contacts Cl, C! just close. The timer cam set screw isthen tightened, cover plate It locked in place by ring 89 and the loommay then be operated. With the crankshaft, and hence the lay, operatingand moving successively through front center (0), top center (90), rearcenter (180), and bottom center (270) posimotion. In the event the tinestions in repetitive cycles, timer cam 03 is rotated synchronouslytherewith, periodically causing closure of the respective pairs ofcontacts CI, C1 and CI, Cl and thereafter allowing opening thereof underthe influence of spring ll. Commencing with the lay at 0 position, withthe fork tines in the fork well and transformer T energized, switch 20is closed but contacts C9, C0 are open and consequently magnet coil M isnot energized. Contacts Cl, C2 are likewise open and coil 00 is notenergized. As the lay moves rearwardly, contacts Cl, C2 close at orabout the time the 45' position is reached. closing the circuit throughcoil ll, and tines l4 commence to rise. The tines rise quickly. causingswitch 20 to assume open circuit condition, and are well above the level.ofthe race plate by the time the lay reaches the position, atapproximately which time contacts C3, C4 close. Closure of the lattercontacts fails to complete the circuit through coil M, however, sincethat circuit is at this time open at switch 20. Filling laying commencesat about 90 position and continues usually until after position, thefilling being laid past the fork well sufiiciently early in the movementof the lay from the 90 to the 270 position to allow deenergization offield coil 40 at about 180 position, and at approximately that timecontacts Cl, C! are opened. The fork tines then move down and are eitherstopped at the level of the race plate by an intact filling or move intothe well if not so stopped, this action being completed by the time thelay reaches the 200 position or shortly thereafter. In the event thetines move into the well, the circuit through coil M is completed byswitch 28' and the loom is stopped through action of the conventionalstop encounter an intact filling, the lay continues to and through the270 position. At about the 300' position, contacts CI, C4 are opened,and the lay continues on toward 360 (0) position. At approximately the320 position, the filling moves out from underthe fork tines and thelatter move down, causing switch 28 to assume the closed circuitcondition. This action is ineifective, however. to cause energization ofcoil M, due to the previous opening of contacts CI, Cl at about the 300position. Upon the lay again reaching the 0 position, the cycle ofoperations is repeated. It will be obvious that screw II and timer cup55 may be adjusted while the loom is in operaton to lengthen or shortenthe period during which the field coil 40 is energized and also to varythe point in the loom cycle at wh ch such energzation commences, to mostadvantageously utilize the time following laying 'of the filling pastthe fork well in initiating operation of the loom stop motion andeffecting loom stopping.

It will be obvious to those skilled in the art that contacts C3, C4 andthe means for actuating and adjusting them may be eliminated from thestop motion magnet circuit if the stop motion mechanism is so arrangedas to be ineffective during the time the filling fork is normally in thewell. I prefer, however, to employ a timing device in the stop motionmagnet circuit to obviate the continual intermittent energization of thestop motion magnet coil and resultant vibration of stop motion parts.

From the above description of the construction and operation of apreferred embodiment of the invention it will be seen that there hasbeen provided for looms a filling motion of simple construction whoseparts are few and small and light in weight, which may be preciselyadiusted and timed with great accuracy while the loom is in operation,whose parts are readily accessible to the loom fixer, and in which theduration of the period during which the fork tines are raised may bereadily varied without change of filling motion cams or other parts.Further it will be seen that there has been provided a filling motionwhich allows ready adjustment to secure the maximum possible timebetween detection of a weft fault and loom stoppage in which to-initiateand effect stopping of the loom. Further it will be seen that there isprovided a filling motion that lends itself to easy incorporation intoexisting as well as new looms, and which in these and other waysachieves the objects of the invention.

Having fully disclosed a preferred embodiment of my invention it will beevident that changes and modifications will occur to those skilled inthe art to which it pertains; and I do not desire to be limited to theparticular physical structure chosen to illustrate the invention, butwhat I claim is:

1. A filling fork structure for a loom including, in combination: a forktine, and means including periodically active interacting magnetic fieldproducing means for actuating said tine.

2. A filling fork structure for a loom includin in combination: a forktine, means responsive to a changing magnetic field to move said tine toactive position, and means producing a changing magnetic field to whichthe first-named means is responsive.

3. A fork filling motion for a loom, comprising, in combination:magnetic-field producing means; filling fork means includingmagneticfield responsive means and a tine moved thereby in response tochanges in the magnetic-field produced by said field producing means;and means causing said changes in the magnetic field produced by saidfield producing means.

4. A fork filling motion for a loom, comprising, in combination:electric coil means arranged to produce upon energization a firstmagnetic field; means capable of producing a second ma netic fieldwithin said first field; a filling fork tine on one of said means toreceive operative movement in response to interaction of said first andsecond magnetic fields; and electrical means periodically energizingsaid electric coil means.

5. A fork filling motion for a loom comprising, in combinationtherewith: eletromagnet means including a magnetizable field piece and aconducting coil on said piece; filling fork means including a tine andan armature carrying said tine and including a short-circuitedconducting coil encircling said field piece; means capable of supplyingfluctuating electric current to said first named conducting coil; andmeans capable of intermittently interrupting the supply of current tosaid first named conducting coil in timed relation to loom operaion.

6. A fork filling motion for a loom. comprising, in combination: a firstmeans producing a first magnetic field; a'second means producing asecond magnetic field having a component interacting with a component ofsaid first magnetic field: structure supporting said first and secondmeans for relative movements therebetween in res onse to changes in theinteracting components of their fields: a aratus causing periodic chanes in said interacting com onents of sa d magnetic fields and therebycausing said relative movements; a filling fork tine; and

structure connecting said tine to one of said means and causing saidtine to move to active position in response to one of said movements.

7. A fork filling motion for a loom comprising, in combination: a forkarmature and a tine carried thereby; means capable, upon change of acondition, of repelling said armature and moving said tine; and meansperiodically causing said change of condition.

8. A fork filling motion fora loom including, in combination therewith:electromagnet means; induction-repulsion means responsive to a change inmagnetic-field produced by the electromagnet means to produce relativemovement therebetween; means supplying fluctuating electric current tosaid electromagnet; means interrupting the supply of said current intimed relation to loom operation; and a filling fork tine carried by oneof said first and second named means and moved thereby upon occurrenceof said relative movement.

9. A center filling fork motion for a loom having a moving lay beam,comprising, in combination therewith: a frame carried by the lay beam;an electromagnet field piece carried by said frame; a first e ctric coilon said field piece; a fork armature'spivotally carried on said frameand including a short-circuited coil encircling said field piece; a forktine carried by said armature; electrical means connected in circuit andcapable of supplying rapidly fluctuating electrical current to saidfirst coil; means operating in timed relation to movement of the laybeam to interrupt and to re-establish said circuit whereby said firstelectric coil is periodically energized to cause repulsion of saidshort-circuited coil and raising of said tine to active position; andmeans operable by said armature and tine to initiate loom stoppage uponabnormal movement of said tine.

10. In a loom having a filling inserting mechanism and means forinitiating the stopping of the loom upon failure of said fillinginserting mechanism properly to insert a pick of filling, meansafiecting said means to initiate stopping which includes a filling forkmotion comprising at least one filling fork tine, a support for saidtine upon which it moves to and from a position to contact the filling,and means for acting through said support for moving the tine to andfrom a position to engage the filling which comprises a magnetic core, acircuit and means for periodically varying current flowing in saidcircuit to induce a magnetic field in said core, and a current conductormovable with said support and so positioned with respect to said core asto have a current induced therein, thereby to set up a second magneticfield in opposition to the magnetic field first mentioned, said opposedmagnetic fields being effective for moving the current conductor andtine support relatively to the said core.

11. In a loom having a filling inserting mechanism and means forinitiating the stopping of the loom upon failure of said filling insertng mechanism properly to insert a pick of filling, means afiecting saidmeans to initiate stopping which includes a filling fork motioncomprising at least one filling fork tine, a support for said tine uponwhich it moves to and from a position to contact the filling, and meansacting through said support for moving the tine to and from a positiontoengage the filling which comprises a magnetic core, a circuitincluding a coil surrounding said core and means for periodicallyvarying current flowing in said cir- 13 cult to induce a magnetic fieldin said core, and a current conducting armature forming a part of saidsupport and movable therewith, said armature being so positioned withrespect to said core as to have a current induced therein, thereby toset up a second magnetic field about the said armature and in oppositionto the magnetic field first mentioned in said core, said opposedmagnetic fields being effective for movin the armature, support and tinerelatively to the core and for the purpose above indicated.

12. In a loom having a filling inserting mechanism and means forinitiating the stopping of the loom upon failure of said fillinginserting mechanism properly to insert a pick of filling, meansaffecting said means to initiate stopping which includes a filling forkmotion comprising at least one filling fork tine, a support for saidtine upon which it moves to and from a position to contact the filling,and means acting through said support for movin the tine to and from aposition to engage the filling which comprises a curved core ofmagnetically permeable material, a circuit including a coil surroundingsaid core adjacent one end thereof and means for periodically varyingcurrent flowing in said circuit to induce a magnetic field in andadjacent said core, and a current conducting armature surrounding saidcore and movable with said support, said armature being adapted to havea current induced therein when the said core is magnetized, thereby toset up a secondary magnetic field about the conductor and in oppositionto the magnetic field primarily induced in said core, said opposedmagnetic fields being effective for moving the current conductor,support and tine relatively to the said core.

13. In a loom having a filling inserting mechanism and means forinitiating the stopping of the loom upon failure of said fillinginserting mechanism properly to insert a pick of filling, meansaffecting said means to initiate stopping which includes a filling forkmotion comprising at least one filling fork tine, a support for saidtine and a pivot upon which said support and tine may be oscillated toand from a position to contact the filling, and means acting throughsaid support and including an arma- 14 ture, a magnetic core, a circuitand means for periodically varying current flowing in said circuit toinduce a primary magnetic field in said core, said armature surroundingsaid core and constituting a short-circuited, non-magnetic conductorwithin which a current is induced as said core is magnetized, saidarmature, when a current is induced therein, having produced therein asecondary magnetic field relatively disposed with respect to the primarymagnetic field so that the two act in opposition for moving the armaturealong the core thereby to swing the support and tine about their pivot.

14. In a loom having a filling inserting mechanism and means forinitiating the stopping of the loom upon failure of said fillinginserting mechanism properly to insert a pick of filling, meansaffecting said means to initiate stopping which includes a filling forkmotion comprising at least one filling fork tine, a support for saidtine upon which it moves to and from a position to contact the filling,and means for acting through said support for moving the tine to andfrom a position to engage the filling which comprises a magnetic core, acircuit and means for periodically Varying current flowing in saidcircuit to induce a magnetic field in said core, which means comprises acircuit interrupter and cam means functioning on a moving part of saidloom which operate in timed relation to the filling inserting movementthereof, and a current conductor movable with said support and sopositioned with respect to said core as to have a current inducedtherein when said core is magnetized, thereby to set up a secondmagnetic field in opposition to the magnetic field first mentioned, saidopposed magnetic fields being effective for moving the currentconductor, support and tine relatively to the said magnetized core.

' GEORGE E. CLENTIMACK.

REFERENCES CITED The following references are of record in the

